Interference and Timing Christine Stewart Objective The objective

Interference and Timing Christine Stewart

Objective § The objective is to impart a basic knowledge of interference engines and timing belts.

Parts of the Engine § Engine Block – the housing of the engine § Cylinder – the cylinder where the piston moves § Piston – a circular block that forces air and fuel in, compresses it, combusts it, then exhausts it (four-stroke engine) § Crankshaft – turns the connecting rod which pushes and pulls the piston

§ Spark plug – creates a spark for combustion of air/fuel mixture § Valves – let fuel in (intake valve) and exhaust out (exhaust valve) § Camshaft – controls the valves (opens and closes them) § Timing Belt – a belt made of rubber that links the camshaft and crankshaft – the camshaft is geared to turn at half the rate of the crankshaft

Non-Interference vs. Interference Engine Source: http: //www. carrsmith. com/timing%20 belt. htm

Interference Engines § The timing belt on any engine is hard to inspect – located under a cover on the front of the engine § Manufacturers will recommend a time interval when the belt should be replaced § On a free-running engine, if the timing belt breaks it won’t cause damage § On an interfering engine, if the timing belt breaks it causes severe damage – the whole engine may need to be replaced

§ For cars with an interfering engine, if timing is incorrect, the pistons and valves collide, and the car will automatically stop working § If a belt is replaced it must be properly synchronized with the movements of the pistons and valves § Timing belt made of rubber with fiberglass or Kevlar fibers in it § Engine must be running well or else the rubber degrades, which can cause severe problems

Conclusion § There are both interfering and noninterfering engines § Interfering engines need to be brought in for check up to make sure the timing belt is still in good order § Timing is extremely important for a smooth-running car

References § § http: //auto. howstuffworks. com/engine. htm http: //en. wikipedia. org/wiki/Timing_belt http: //www. carrsmith. com/timing%20 belt. htm http: //www. familycar. com/Car. Care/Gates. Fra me. htm